Read books of
this guy and I'm sure you will get great value for time spend to it. Oh yes, he created Tarzan too
It is also really nice how different series are at some point connected to others.
If you then read books of H.G Wells you will found out that from quite many they have made Hollywood blockbusters. But I find his books bit less interesting that that previous guy's books.
Did I mention I do like old good scifi without horror elements best?